"It's going to be a costly mistake that someone's going to really regret tomorrow, but it's nothing that can't be fixed and there's no major damage," said Willis Middle School Principal Lisa Severns.
School officials say they got a call from their alarm company, which alerted them to the incident, but they're not certain what time this took place.
If you have any information about this crime, you're asked to call the Montgomery County Sheriff's Office.
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